<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>
  <body>
    <div id="app">
      <input type="text" v-bind:value="str" v-on:input="handleInput" />
      <p>{{ str }}</p>
    </div>

    <script src="../Vue.js"></script>
    <script>
      const vm = new Vue({
        el: "#app",
        data: {
          str: "123",
        },
        methods: {
          handleInput(e) {
            this.str = e.target.value;
          },
        },
      });
    </script>
  </body>
</html>
